Inside a uniform shell

Inside a uniform sphericall shell

Inside a uniform spherical shell

Inside a uniform spherical shell

A : The gravitational field intensity is zero everywhere inside a uniform spherical shell R: The net force on a point mass inside a uniform spherical shell is zero everywhere .

A particle placed 1.inside a uniform spherical shell of mass M, but not at the center 2.inside a uniform spherical shell of mass M, at the center 3.outside a uniform spherical shell of mass M, a distance r from the center 4.outside a uniform solid sphere of mass M, a distance 2r from the center If F_1,F_2,F_3 and F_4 are gravitational forces acting on the particle in four cases.